Recent changes to the outside appearance of cars and trucks have been greatly influenced by aerodynamic requirements. With respect to such aerodynamic requirements, significant changes have taken place in the manner of mounting of windshield glass to a vehicle body.
One major change has been from a gasket-type mounting of a windshield which yields a definite offset between the glass surface and the body surface, to a bonded glass mounting which provides a glass surface and body surface in nearly the same plane. In such bonded mounting, a small extruded vinyl trim strip is positioned within a channel between the glass and body panels and extends over the glass and body panels after the glass is adhesively bonded in place, to provide a finished appearance to the juncture. The adhesive layer used to retain the glass in place is also used to retain the trim strip in place.
Further, more recent advancements have introduced an encapsulated glass process. This process includes the molding of a plastic trim strip onto the periphery of the glass, using an injection molding process in which the glass is placed into the mold during the molding process. This method provides a single unit for installation with excellent dimensional tolerances along the perimeter of the assembly. However, butyl or other adhesives, such as polyurethane, are still used to retain the encapsulated glass within the windshield mask.